<!DOCTYPE html>
<html lang=en>
<head>
    <meta charset=utf-8>
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0">
    <script src="https://cdn.jsdelivr.net/gh/eduardolundgren/tracking.js/build/tracking-min.js"></script>
    <script src="https://cdn.jsdelivr.net/gh/eduardolundgren/tracking.js/build/data/face-min.js"></script>
</head>
<style>
    .checkagain {
        background-color: #f44242;
        height: 35px;
        position: fixed;
        width: 90%;
        margin-left: 5%;
        transform: translateY(2.5%);
        border-radius: 3px;
        font-size: 14px;
        text-align: center;
        line-height: 35px;
        bottom: 70px;
        color: #ffffff;
    }
    .videodiv {
        width: 200px;
        height: 200px;
        background-color: #999999;
        border-radius: 100px;
        margin-top: 30px;
        margin-left: calc((100% - 200px) / 2);
        overflow: hidden;
    }
    .video {
        position: relative;
        left: -100px;
    }
</style>
<body>
<div class="videodiv">
    <video id="video" controls="false" muted="true" width="400px" class="video"></video>
</div>
<div class="checkagain" onclick="startRecord()">开始录制</div>
<div class="checkagain" style="bottom: 25px;" onclick="stopRecord()">结束录制</div>
</body>

</html>